Undefined variable: pdo, call to a member function prepare() on null

Question

I was following a video and double checking all code and everything seems to be the same yet I get these errors.

Errors:

Notice: Undefin

Answer 1

As stated in comments, in OOP, you need to use $this->pdo passing the object's property for it, instead of the variable $query = $pdo-> since you've construct'ed it in:

public function __construct($pdo)
{
    $this->pdo = $pdo;
    ^^^^^^^^^^
}

I.e.:

$query = $this->pdo->prepare